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21.
CI Acid Black 210 was microencapsulated into liposomic systems, and the effects of the microencapsulation on dyebath exhaustion, depth of shade, colour fastness properties and through‐dyeing of chrome‐tanned leather were studied. In comparison with the original dyestuff form, the microencapsulated dye showed a deeper shade and a greater depth of through‐dyeing. Exhaustion and colour fastness values were the same.  相似文献   
22.
Doxorubicin is a commonly used antineoplastic agent in the treatment of many types of cancer. Little is known about the interactions of doxorubicin with cardiac biomolecules. Serious cardiotoxicity including dilated cardiomyopathy often resulting in a fatal congestive heart failure may occur as a consequence of chemotherapy with doxorubicin. The purpose of this study was to determine the effect of exposure to doxorubicin on the changes in major amino acids in tissue of cardiac muscle (proline, taurine, glutamic acid, arginine, aspartic acid, leucine, glycine, valine, alanine, isoleucine, threonine, lysine and serine). An in vitro interaction study was performed as a comparison of amino acid profiles in heart tissue before and after application of doxorubicin. We found that doxorubicin directly influences myocardial amino acid representation even at low concentrations. In addition, we performed an interaction study that resulted in the determination of breaking points for each of analyzed amino acids. Lysine, arginine, β-alanine, valine and serine were determined as the most sensitive amino acids. Additionally we compared amino acid profiles of myocardium before and after exposure to doxorubicin. The amount of amino acids after interaction with doxorubicin was significantly reduced (p = 0.05). This fact points at an ability of doxorubicin to induce changes in quantitative composition of amino acids in myocardium. Moreover, this confirms that the interactions between doxorubicin and amino acids may act as another factor most likely responsible for adverse effects of doxorubicin on myocardium.  相似文献   
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置换通风空调房间室内空气品质研究   总被引:2,自引:0,他引:2  
本文选用一应用置换通风方式的典型办公室房间作为研究对象,应用数值模拟方法,从室内空气温度分布、速度场、PMV-PPD及空气龄几方面模拟研究了置换通风条件下室内空气品质。结果表明置换通风方式下空调房间具有较好的热舒适环境和良好的室内空气品质。  相似文献   
25.
Ideal switches are rarely modelled in network analysis because inconsistent conditions can occur at the instant of switching. This causes standard integration routines to fail. If the initial conditions can be determined, the use of ideal switches can considerably speed up analysis and can make the results easier to understand. This paper, partly a review, presents a method which can handle ideal switching, inconsistent initial conditions, Dirac impulses and signals with discontinuities. It is applicable to networks containing linear or non-linear elements.  相似文献   
26.
Haloalkane dehalogenases catalyse environmentally importantdehalogenation reactions. These microbial enzymes representobjects of interest for protein engineering studies, attemptingto improve their catalytic efficiency or broaden their substratespecificity towards environmental pollutants. This paper presentsthe results of a comparative study of haloalkane dehalogenasesoriginating from different organisms. Protein sequences andthe models of tertiary structures of haloalkane dehalogenaseswere compared to investigate the protein fold, reaction mechanismand substrate specificity of these enzymes. Haloalkane dehalogenasescontain the structural motifs of /ß-hydrolases and epoxidaseswithin their sequences. They contain a catalytic triad withtwo different topological arrangements. The presence of a structurallyconserved oxyanion hole suggests the two-step reaction mechanismpreviously described for haloalkane dehalogenase from Xanthobacterautotrophicus GJ10. The differences in substrate specificityof haloalkane dehalogenases originating from different speciesmight be related to the size and geometry of an active siteand its entrance and the efficiency of the transition stateand halide ion stabilization by active site residues. Structurallyconserved motifs identified within the sequences can be usedfor the design of specific primers for the experimental screeningof haloalkane dehalogenases. Those amino acids which were predictedto be functionally important represent possible targets forfuture site-directed mutagenesis experiments.  相似文献   
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The fetal magnetoencephalogram (fMEG) is measured in the presence of large interference from the maternal and fetal magnetocardiograms. This interference can be efficiently attenuated by orthogonal projection of the corresponding spatial vectors. However, the projection operators redistribute the fMEG signal among sensors. Although redistribution can be readily accounted for in the forward solution, visual interpretation of the fMEG signal topography is made difficult. We have devised a general, model-independent method for correction of the redistribution effect that utilizes the assumption that we know in which channels the fMEG should be negligible (such channels are distant from the known fetal head position). In a simplified case where the fMEG can be explained by equivalent current dipoles, the correction can also be obtained from fitting the dipoles to the fMEG signal. The corrected fMEG signal topography then corresponds to the dipole forward solution, but without orthogonal projection. We illustrate the redistribution correction on an example of experimentally measured flash evoked fMEG.  相似文献   
29.
Development of direct competitive enzyme-linked immunoadsorbent assays (ELISAs) based on polyclonal and monoclonal antibodies raised against 4-n-alkylphenol hapten mimics is described. A strong tendency to recognize 4-nonylphenol (NP) and 4-octylphenol (OP) as a total analyte amount was indicated by cross-reactivity pattern established for two polyclonal antibodies. These antibodies were employed for development of class-selective assays exhibiting IC(50) values around 40 microg.L(-1) for technical 4-NP. Specificity of the monoclonal antibody 4H6 and additional two polyclonal antibodies allowed sensitive detection of linear long-chain forms of 4-n-alkylphenols (4-n-AP). The assays incorporating these antibodies offer a potential for detecting the minor fraction of NP/OP isomer spectrum having IC(50) = 11.5 microg.L(-1) for 4-n-NP. No cross-reactivity interference was indicated for linear alkylbenzene sulfonates and phenolic compounds. To interpret the measured data in terms of analytical equivalents, a reliable relationship between the assay responses and AP content of contaminated samples should be verified and validated.  相似文献   
30.
The force-balanced piston gauge is a primary vacuum standard developed in the 1990s. The general principle of the instrument was first presented in Ooiwa A (Metrologia 30 (1994) 607). Non-rotating piston is connected to an electronic dynamometer and centered by means of transient gas flow in a double tapered gap between piston and cylinder. More details about it can be found in Delajoud, Girard(NCSL International Workshop and Symposium 2002; Vakuum Forschung Praxis 15 (2003) 24) and Tesar, Prazak(Vacuum 67 (2002) 307).Czech Metrology Institute developed its own method of the primary traceability of this instrument through the determination of its effective area. In this paper, there will be described experimental setup of this comparison as well as the experimental results from the traceability calibrations of the effective area in gauge and absolute mode using experimental method of hydrostatic comparison with the classical rotating piston balances and a digital non-rotating piston balance. It will, of course, include the uncertainty budget of this way of traceability and the final uncertainty of the pressure generation of the instrument.  相似文献   
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